The basic function of damping is commonly realized by the flow of fluid through a restricted path. A damper often uses a piston enclosed in a cylinder to push fluid through an orifice, or a set of orifices. The restricted fluid flow creates a force that opposes the movement of the piston. The magnitude of the opposing force is a function of the orifice(s) size and the rate of the piston movement. The orifice size and/or quantity of orifices may establish the range of damping forces.
The manufacture of dampers requires maintaining a stock of different fluid metering valve assemblies. The manufacturing tolerances of the components need to be maintained within ranges that are specific to each valve assembly. The valve assemblies/valve blocks are assembled into dampers to establish its damping performance. Each different metering valve block produces a damper with a specific damping characteristic. Manufacturing and maintaining an inventory of a variety of valves and their selective assembly into dampers may add cost to the manufacture of dampers.